Actuator monitoring system using inertial sensors
Sensor data is received from an inertial measurement unit on a vehicle. An observed attitude and an observed attitude rate of the vehicle are determined based on the sensor data. Using a model associated with a vehicle failure mode, an expected attitude and an expected attitude rate of the vehicle are determined. A malfunctioning rotor is determined based on the observed attitude, the observed attitude rate, the expected attitude, and the expected attitude rate. In response to identifying the malfunctioning rotor, a responsive action is performed, including by updating a geometry matrix so that at least one non-malfunctioning rotor in the plurality of rotors compensates for the malfunctioning rotor.
1. A system, comprising:
a processor; and
a memory coupled with the processor, wherein the memory is configured to provide the processor with instructions which when executed cause the processor to:
receive sensor data from an inertial measurement unit on a vehicle;
determine an observed attitude and an observed attitude rate of the vehicle based at least in part on the sensor data;
determine an expected attitude and an expected attitude rate of the vehicle based at least in part on a model associated with a vehicle failure mode;
identify, from a plurality of rotors associated with the vehicle, a malfunctioning rotor based at least in part on the observed attitude, the observed attitude rate, the expected attitude, and the expected attitude rate; and
in response to identifying the malfunctioning rotor, perform a responsive action, including by updating a geometry matrix, which is used to generate a plurality of actuator commands for the plurality of rotors, so that at least one non-malfunctioning rotor in the plurality of rotors compensates for the malfunctioning rotor.
2. The system recited in claim 1 , wherein updating the geometry matrix includes updating a previous geometry matrix with a precomputed geometry matrix while the vehicle is in flight.
3. The system recited in claim 1 , wherein updating the geometry matrix includes changing, in real time, one or more force distributions so that the at least one non-malfunctioning rotor in the plurality of rotors compensates for the malfunctioning rotor.
4. The system recited in claim 1 , wherein:
the malfunctioning rotor is associated with a first region of the vehicle; and
updating the geometry matrix includes increasing an authority of a second region of the vehicle in response to detection of the malfunctioning rotor in the first region.
5. The system recited in claim 1 , wherein identifying the malfunctioning rotor includes performing tie breaking using one or more test commands.
6. The system recited in claim 1 , wherein identifying the malfunctioning rotor includes performing tie breaking among a plurality of equally possible malfunctioning rotors using one or more test commands, including by:
sending a first test command to a first possible malfunctioning rotor in the plurality of equally possible malfunctioning rotors;
receiving first test sensor data from the inertial measurement unit in response to the first test command;
sending a second test command to a second possible malfunctioning rotor in the plurality of equally possible malfunctioning rotors;
receiving second test sensor data from the inertial measurement unit in response to the second test command; and
selecting from the plurality of equally possible malfunctioning rotors using the first test sensor data and the second test sensor data.
7. A method, comprising:
receiving sensor data from an inertial measurement unit on a vehicle;
determining an observed attitude and an observed attitude rate of the vehicle based at least in part on the sensor data;
determining an expected attitude and an expected attitude rate of the vehicle based at least in part on a model associated with a vehicle failure mode;
identifying, from a plurality of rotors associated with the vehicle, a malfunctioning rotor based at least in part on the observed attitude, the observed attitude rate, the expected attitude, and the expected attitude rate; and
in response to identifying the malfunctioning rotor, performing a responsive action, including by updating a geometry matrix, which is used to generate a plurality of actuator commands for the plurality of rotors, so that at least one non-malfunctioning rotor in the plurality of rotors compensates for the malfunctioning rotor.
8. The method recited in claim 7 , wherein updating the geometry matrix includes updating a previous geometry matrix with a precomputed geometry matrix while the vehicle is in flight.
9. The method recited in claim 7 , wherein updating the geometry matrix includes changing, in real time, one or more force distributions so that the at least one non-malfunctioning rotor in the plurality of rotors compensates for the malfunctioning rotor.
10. The method recited in claim 7 , wherein:
the malfunctioning rotor is associated with a first region of the vehicle; and
updating the geometry matrix includes increasing an authority of a second region of the vehicle in response to detection of the malfunctioning rotor in the first region.
11. The method recited in claim 7 , wherein identifying the malfunctioning rotor includes performing tie breaking using one or more test commands.
12. The method recited in claim 7 , wherein identifying the malfunctioning rotor includes performing tie breaking among a plurality of equally possible malfunctioning rotors using one or more test commands, including by:
sending a first test command to a first possible malfunctioning rotor in the plurality of equally possible malfunctioning rotors;
receiving first test sensor data from the inertial measurement unit in response to the first test command;
sending a second test command to a second possible malfunctioning rotor in the plurality of equally possible malfunctioning rotors;
receiving second test sensor data from the inertial measurement unit in response to the second test command; and
selecting from the plurality of equally possible malfunctioning rotors using the first test sensor data and the second test sensor data.
13. A computer program product, the computer program product being embodied in a non-transitory computer readable storage medium and comprising computer instructions for:
receiving sensor data from an inertial measurement unit on a vehicle;
determining an observed attitude and an observed attitude rate of the vehicle based at least in part on the sensor data;
determining an expected attitude and an expected attitude rate of the vehicle based at least in part on a model associated with a vehicle failure mode;
identifying, from a plurality of rotors associated with the vehicle, a malfunctioning rotor based at least in part on the observed attitude, the observed attitude rate, the expected attitude, and the expected attitude rate; and
in response to identifying the malfunctioning rotor, performing a responsive action, including by updating a geometry matrix, which is used to generate a plurality of actuator commands for the plurality of rotors, so that at least one non-malfunctioning rotor in the plurality of rotors compensates for the malfunctioning rotor.
14. The computer program product recited in claim 13 , wherein updating the geometry matrix includes updating a previous geometry matrix with a precomputed geometry matrix while the vehicle is in flight.
15. The computer program product recited in claim 13 , wherein updating the geometry matrix includes changing, in real time, one or more force distributions so that the at least one non-malfunctioning rotor in the plurality of rotors compensates for the malfunctioning rotor.
16. The computer program product recited in claim 13 , wherein:
the malfunctioning rotor is associated with a first region of the vehicle; and
updating the geometry matrix includes increasing an authority of a second region of the vehicle in response to detection of the malfunctioning rotor in the first region.
17. The computer program product recited in claim 13 , wherein identifying the malfunctioning rotor includes performing tie breaking using one or more test commands.
18. The computer program product recited in claim 13 , wherein identifying the malfunctioning rotor includes performing tie breaking among a plurality of equally possible malfunctioning rotors using one or more test commands, including by:
sending a first test command to a first possible malfunctioning rotor in the plurality of equally possible malfunctioning rotors;
receiving first test sensor data from the inertial measurement unit in response to the first test command;
sending a second test command to a second possible malfunctioning rotor in the plurality of equally possible malfunctioning rotors;
receiving second test sensor data from the inertial measurement unit in response to the second test command; and
selecting from the plurality of equally possible malfunctioning rotors using the first test sensor data and the second test sensor data.